The NYPD is set to announce Thursday new rules on the use of force by cops, including better and more complete reporting by officers involved in such incidents, law enforcement officials said.

Commissioner William Bratton will reveal the new policy, which has been some nine months in the making, at an afternoon news briefing at police headquarters. The revision calls for major changes in the Patrol Guide, the bible of police practices and procedures, the officials said.

The NYPD has been under attack over the use of force by cops since the 2014 death of Eric Garner on Staten Island, who died after what the city medical examiner said was a police chokehold. Critics have contended that the police have a poor system of documenting use of force cases.

Under the new rules, which are expected to take effect on Jan. 1, cops will be required to intervene in cases where they see excessive use of force being used by fellow officers, said an official briefed on the subject.

In addition to better documenting of use of force by officers, the NYPD will also be reporting cases where force is used against police officers by members of the public, said the official.

As part of the changing reporting requirements, officers will be expected to document as use of force any instance where they had to restrain or grapple with an emotionally disturbed person, something that isn't done now, said the official.